To test a drug intended to increase memory capacity, 80 subjects were randomly given a pill that either contained a drug or was a placebo. After ten minutes, the subjects were asked to look at a poster with pictures of 20 common objects for five minutes. After waiting ten minutes, the subjects were asked to list as many of the objects as they could recall. For the 44 subjects who took the drug, 75% were able to list at least half of the objects. For the 36 subjects who took the placebo, 50% were able to list at least half of the objects. Let p1 be the population proportion of subjects who took the drug and were able to list at least half of the objects, and let p2 be the population proportion of subjects who took the placebo and were able to list at least half of the objects. To test the alternative hypothesis Ha:p1p20, what are the critical values? Use the level of significance =0.05 and round your answers to two decimal places.

zz0.10	zz0.05	zz0.025	zz0.01	zz0.005
1.282	1.645	1.960	2.326	2.576